'89 Burb: Height sensing proportioning valve after lift?

[Larry]

What are you guys doing about the height sensing proportioning valves on the back of square body style Suburban’s after lifting?

I’m debating if I want to rework the arm to fit the freshly swapped in 14 bolt ff and lift or unhook it all together and just figure out how to lock the adjustment for a level position. Curious to hear what you all have done with these dumb things.

 

[dremu]

Didn't know there were any still in operation. I believe standard practice is to bypass them and be done. Either replace the brake line or just get a coupler, and bleed the rear circuit.

-- A

 

[Flamin' Fast]

what exactly is this valve supposed to do? give more rear brake when loaded?

 

[dremu]

what exactly is this valve supposed to do? give more rear brake when loaded?

More like less when empty. It can only reduce pressure.

-- A

 

[Fordum]

Yep, pretty much. Its useful under certain circumstances, but if you put a lift on it, then even if you extend it, its not going to be as good at actually sensing a load.

 

[snowdriver]

the blazers dont have these do they?? never seen that before

 

[86454K30]

The rear brake proportioning valve only came on c/k20 with the JB8 brake option and on all 30 series trucks. The concept is that as the truck is loaded down it increase the brake pressure for the rear brakes.

On the K30's and K20's I have lifted I have eliminated the valve. It seems to give you better brakes IMO. On the one I have now I removed the line from front of the truck to the valve and hooked the new SS brake hose up...eliminating the valve.

I have before "raised" the mounting location off the axle but, I really don't think its worth the hassle.